The present embodiments relate to a method and a device for display of dose values for planning an irradiation.
X-rays and particle rays are used for the treatment of tumors. Such treatment requires an irradiation plan that defines the time at which and the intensity with which the radiation is applied. To create an irradiation plan, the position and also the form of the examination volume (e.g., the tumor) is to be determined. Such a determination may be undertaken with an imaging method such as computed tomography (CT) or magnetic resonance tomography (MRT).
An objective of the irradiation plan is to optimize the irradiation with respect to dose distribution. In the treatment of tumors, the desire is for as much as possible of the dose to be taken up by the tumor and as little as possible of the dose to be taken up by surrounding, healthy tissue. Irradiation methods may also be used in non-therapeutic areas (e.g., in the irradiation of phantoms or non-living bodies as part of research work, or in the irradiation of materials). In such cases, an optimization of the dose distribution is desirable.
The dose values determined before the actual irradiation are displayed graphically, so that the irradiation plan may be assessed. The form in which the dose values are displayed may be such that the dose values are able to be assessed as quickly and as reliably as possible. The important information about the distribution of the dose is to be displayed, and the display is simplified far enough for the significant aspects of the dose distribution to be detected quickly and reliably.
The publication by Rieder et al., “Visual Support for Interactive Post-Interventional Assessment of Radiofrequency Ablation Therapy,” Eurographics/IEEE-VGTC Symposium on Visualization, Volume 29, Number 3 (2010), discloses a method for visualizing the map of a tumor for reliable assessment of an ablation therapy. In ablation therapy for treating liver tumors, electrical energy is created locally by electrodes, so that tumor cells are destroyed locally by the resistive heat arising. To be able to plan the ablation therapy and assess the success of the treatment, CT images of the tumor are recorded before and after the therapeutic intervention. This method includes, based on the CT images, the color coding of the ablation state of the tumor in accordance with the traffic light colors green, orange and red. The 2D slice images of the tumor are color-coded and are used for an additional intuitive visualization. Then the color coding is mapped onto the surface of a rendered 3D volume of the tumor. The surface of the tumor is also represented in the form of a 2D map. This may be achieved by spherical parameterization as well as by the subsequent smoothing of the surface.